1. Field of the Invention
The present invention relates to a cell analyzer, and a cell analyzing method.
2. Description of the Related Art
An analyzer for automatically analyzing the cells of the subject, and providing information related to canceration of the relevant cells (see e.g., US2008-108103A1). US2008-108103A1 discloses a device for flowing a measurement specimen containing the cells harvested from the subject to a flow cell, irradiating light on the measurement specimen flowing through the flow cell to acquire a scattered light signal for the individual cell, extracting a feature parameter by analyzing the waveform of each scattered light signal, and discriminating cancer/atypical cells from a plurality of cells using the feature parameter.
A basal layer, a parabasal layer, an intermediate layer, and a surface layer are formed in order from the basement membrane side in a uterine cervix. In the tissue diagnosis of the uterine cervix, the process from the normal state to canceration includes a plurality of stages of “Normal”, “CIN1”, “CIN2”, “CIN3”, and “Cancer” in order from the normal state. “CIN1” is a state in which the atypical cell is growing in one third from the basal layer toward the surface layer, “CIN2” is a state in which the atypical cell is growing in two thirds from the basal layer toward the surface layer, and “CIN3” is a state in which the atypical cell is growing over substantially entirely from the basal layer to the surface layer. In the process of becoming cancer, the basal cell acquires dysplasia and becomes the atypical cell. The atypical cell acquires the growth ability, and occupies from the basal layer side to the surface layer side. Thus, precancerous lesion appears in the early stage on the basal cell side.
The basal cell of the uterine cervix is the bottommost layer of the epidermis and therefore difficult to collect, and such collection involves pain to the subject, and thus the basal cells are not generally harvested. Therefore, the epidermal cells of the uterine cervix that can be harvested from the subject include the parabasal cell, the intermediate layer cell, and the surface layer cell. In other words, in the process in which the cancer progresses in the epidermal cells that can be harvested, the precancerous lesion appears at an early stage in the parabasal cell.
In order to start the treatment of cancer at an early stage, detection of the precancerous lesion is desirable at an initial stage of cancer such as from “CIN2” to “CIN3”. However, in the conventional analyzer such as the analyzer described in US. Application Publication No. 2008/108103A, the possibility of precancerous lesion and cancer may not be appropriately determined unless the collection of cells useful in the determination of the precancerous lesion is appropriately carried out at the time of harvesting the epithelial tissue from the uterine cervix.